1. Field of the Invention
This invention relates in general to hand tools, and more particularly to hand tools for driving nails and drywall anchors.
2. Description of Related Art
There are many circumstances in which it is difficult to drive a nail or a drywall anchor, particularly using a hammer. For example, a vast number of individuals do not have experience using a hammer, and when a small nail needs to be placed on a wall—the inexperienced individual might end up hurting his fingers or damaging the wall with the hammer.
Hand held nail drivers have been devised for use in circumstances in which a hammer is impractical. For example, U.S. Pat. No. 4,483,475, issued Nov. 20, 1984, to Whitaker, discloses a simple hand held nail driver. The Whitaker device includes a cylindrical guide tube and a plunger rod. A handle is mounted on one end of the plunger rod, and the plunger rod is inserted into the guide tube. A nail is placed into the guide tube, and the handle is moved to cause the plunger rod to strike the nail, driving the nail into a surface. The guide tube is then held in place, as the handle is pulled back to retract the plunger rod from the guide tube.
Nail drivers having elongated tubular bodies receiving the fastener and a slidable impact rod are well known in the art, as shown in the following U.S. patents:
  608,555NazelAug. 02, 18982,430,532RayburnNov. 11, 19472,624,879BairdJan. 13, 19533,036,482KenworthyMay 29, 19624,316,513HarrisFeb. 23, 19824,562,948FloydJan. 07, 19864,709,841WollarDec. 01, 1987
Furthermore, the following patents disclose impact fastener driver tools having magnetic heads for holding a fastener of ferro-magnetic material while it is being driven into a work surface:
  541,038ClarkJun. 11, 18951,127,838WillersFeb. 09, 19152,666,201Van OrdenJan. 19, 19543,979,040DeninSep. 07, 19764,299,021WilliamsNov. 19, 1981
While the impact fastener driver tools disclosed in the prior art appear suitable for their intended purposes, there exists a need for an improved impact fastener driver tool that is simple, comfortable and easy to user, and simply adaptable for use with fasteners of different length and diameter.